Back-pressure valve.



G. C. NEIGHBORS.

BACK PRESSURE VALVE. v APPLIUATION FILED imo. 1s, 190s.

Patented Jn. 18, 1910.

@Vi h1 una EHARLES C. NEIGHBOBS, F SAN ANTONIO, TEXAS.

BACK-PRESSURE VALVE Specication of Letters -Patent.

Patented ian. 1s, 1910.

Application led December 18, 1908. Serial No. 468,216.

To all 'whom 'it concern: l

Be it known that I, CHARLES C. NEIGH- Bons, a citizen of the United States, residing at San Antonio, in the county of Bexar and y`State of Texas, have invented a new and useful Back-Pressure Valve, of which the following is a specification.

By way of explanation, I will state that, in well drilling operations, after the backpressure valve has been placed, it frequently becomes'necessary to remove the same,when, for example, the operator wishes to deepen the well. The common practice in such instances is-to drill out the valve, a practice fraught with much annoyance, and, not infrequently, r'esultingf'in the loss of the well.

It is the object of this invention to provide a back-pressure valve which may be removed from the well with facility and despatch.

"With this and other objects in view, as will hereinafter more fully appear, the invention consists in the novel construction and arrangement of parts hereinafter described, delineated in the accompanying drawings, and particularly pointed out in the appended claims, it bein-g understood that, within the scope of the claims divers changes in the form, proportions, size and minor details of the structure may be made,` withoutdeparting from the spirit or sacri-` cing any of the advantages of the invent Similar numerals lof reference are employed to denote corresponding parts throughout the several ligures of the drawgleferring now to the accompanying drawings 2`Figure 1 is a vertica longitudinall section through a section of well-tubing in which my invention is mounted: Eig. 2 is a transverse section passed through Fig. 1 in the line-A-B: Fig. 3 is a detail perspective, showing the 4annular member 4: Fi 4 is a detail perspective, showing the seat 'L and the accessory parts thereby carried. v

` In the accompanying drawings the numerals 1 and 2 designate sections of tubing, threaded at their adjacent ends in the ordina manner, and united by a coupling 3.

n carrying out the invention, I rovide an annular member 4, having a cylindrical outer face 5, and aA conical downwardly,

flaring inner face 6, both of the faces 5 and 6 being threaded. -I have further shown a seat- 7, having a threaded, conical outer ed e 8 arran d to e e the face 6 of the gannlilar meier 4. I lTaegseat 7 is provided with a centralopening 11, and, disposed about the central opening 11, are other openings 10, extending through `-the seat 7. A headed bolt 12 is shown having a threaded terminal arranged to engage the central opening 11 in the seat 7. The valve proper 13 has a central opening arranged to engage the bolt 12, whereby the said valve 13 may be slidably mounted upon the bolt 12. A resilient element 14 is shown, having its lower terminal in contact with the blt 12, its upper terminal bearing against the valve 13, and serving to force the same upward, closing normally the apertures 10.

The upper face of the seat 7 is arranged to engage a rotating tool, wherebythe said seat 7 may be turned downward, and to this A end I have attached the upstanding lugs 9 to the seat.

The manner of assembling myinvention is as follows Let it be supposed 'that the coupling 3 is mounted upon the member .2. The annular member 4 is then rotated into the coupling 3 and brought into contact with the terminal of the tubing 2, the other parts of the device being carried by the annular member 4, as shown in Fig. 1. The member 1 is then rotated within the coupling 3 to engage the annular member 4. Now, when it is desired to remove the back-pressure valve from the well, a fish-tail bit orlike device is lowered into the well, and rot-ated until it engages the lugs 9. Continued rotation will unscrew the seat 7 r`from the annular member 4, whereupon tHe-said seat 7 and the valve thereby` carried, will drop tothe `bottom of the pipe, where it may readily be shoved aside into the soft material.

-I have made the face 6 of the member 4 conical, and l'arranged the face 8 of the seat 7 of the same shape, in order that the seat 7 may not accidentally be rotated upward through the annular member 4.

coupling internally threaded; an annular` member disposed within the .coupling and threaded toengage the same, the said annular member havin Haring, threaded, inner face; pipe sections threaded for insertion into the ends of .the coupling and rotatable into terminal abutment wlth the annular member; a conical, valved member inserted in the annular member and threaded to en age the'same; and

means carriedV bythe v ved member where,

a conical, downwardly A Maese In testimonj that-.l claim the-foregoing-l as my own, I have hereto aiiied my signature 1n the presence of two witnesses.

Witnesses:

J. l. NICHOLLS, En. A. CHRISTIAN. 

